An Exploratory Proof of Concept Study to Assess the Pharmacokinetics/Pharmacodynamics (PK/PD) of Nemolizumab in Adult Participants With Chronic Pruritus of Unknown Origin (CPUO)

Inclusion Criteria: * Participants are eligible to be included in the study only if all of the following criteria apply: 1. Participant must be 18 years of age or older. 2. Participants with chronic pruritus on normal-appearing skin (except for dry skin or excoriations) for at least 6 months before the screening visit. 3. Chronic pruritus considered of unknown origin (i.e., without a clear association to another condition or medication) as assessed by the investigator at baseline. 4. The pruritus must affect at least 4 of the following body areas: left lower limb, right lower limb, l…